Hi I Have A Black Dot On My Eye Its

Hi I have a black dot on my eye its on the top I wasn't sure what it is. Last week my whole eye turned blood red and I thought it was my contacts so I kept them out for a couple days and the eye stayed red for about 3 day after then it calmed down, but now I put a new pair of contacts that I just got from the eye doctor and it started getting red and hurting so I took them out, but then I really looked at my eye and when I lifted my eye lid up I saw a black dot on the top on the white part of my eye what could it be?